Numerous physical quantity sensors have a temperature characteristic, and an offset and sensitivity of a sensor signal output by the physical quantity sensor vary with temperature. A sensor apparatus disclosed in PTL 1 includes a temperature sensor that outputs a temperature signal corresponding to an ambient temperature of the physical quantity sensor, and obtains A/D conversion values of the sensor signal and the temperature signal by selectively using one A/D converter. The sensor apparatus performs temperature correction for the A/D conversion value of the sensor signal with the use of the A/D conversion value of the temperature signal.
In the conventional configuration described above, the A/D conversion of the temperature signal, the A/D conversion of the sensor signal, and the temperature correction process are sequentially performed. For that reason, a delay corresponding to sum of at least an A/D conversion time and a temperature correction calculation time of the sensor signal occurs until A/D conversion data subjected to temperature correction is obtained since the A/D conversion of the sensor signal starts (sample & hold starts). The above delay time is not reduced even if the above configuration changes to a configuration in which a dedicated A/D converter is provided for each of the physical quantity sensor and the temperature sensor.
In the temperature correction process, there is a need to correct the offset and an inclination of the A/D conversion data. Those correction calculations include four arithmetic operations, and therefore require a time. In particular, the calculation time increases in multiplication and division. As a result, the delay time since the A/D conversion of the sensor signal starts (sample & hold starts) until the A/D conversion data subjected to the temperature correction is output increases, and high speed processing of a control device that operates with the sensor signal as an input signal is prevented.